So in my mind, float is worth somewhere between 0.4-0.75X depending on one's assumptions.

Seems reasonable.

For those who disagree, you may just be talking at cross purposes: there is a difference between valuing the assets provided by the float, valuing those assets in combination with the offsetting float liability and restrictions, and valuing those two along with the (for Berkshire, profitable) insurance operation that provides the float.

Setting aside the value of the active insurance operation and its profits, consider:

A boring new corporate loan is worth nothing, net, since you get the cash and you get the liability. Maybe you'll invest that money well, maybe you'll invest it badly, but the moment you draw the loan it's a wash and adds nothing to the firm's value.

Float by itself is very much like an interest free loan. It's better because of the lack of interest cost. But as with any loan, you still get both the cash and the liability.

Float has a different set of strings attached: you might need to repay quite a big chunk of the principal in any given year, or not: it's not known. You might be able to keep it more or less forever, or it might run off slowly over time. You'll have to keep a lot of it in super liquid paper that on average has zero real return after tax, so some portion of the asset side has zero return for you and is thus worth nothing to you beyond its ability to pay off the offsetting liability.

There is no doubt at all that $100bn in float-generated cash that comes with $100bn in liability, taken together (but without the underwriting operation and its potential profit), is plainly worth less than $100bn in cash with no corresponding deferred liability or payback requirements or liquidity restraints or regulatory restrictions etc. I mean, obviously.

Similarly, the combination is worth much more than zero because some of it can be invested over long periods with a decent return that you get to keep, and you don't have to make interest payments. It's just a matter of assessing how much more than zero, and how much less than an equivalent amount of cash without a corresponding deferred liability and restrictions.

If you think about what each of you is discussing--the float asset, the float asset plus its liability, or both of those plus the underwriting operation--it's likely there isn't much disagreement.

Jim